diff options
Diffstat (limited to 'arch/riscv/include/asm/timex.h')
| -rw-r--r-- | arch/riscv/include/asm/timex.h | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/timex.h b/arch/riscv/include/asm/timex.h index a3fb85d505d4..ab104905d4db 100644 --- a/arch/riscv/include/asm/timex.h +++ b/arch/riscv/include/asm/timex.h @@ -10,6 +10,44 @@ typedef unsigned long cycles_t; +#ifdef CONFIG_RISCV_M_MODE + +#include <asm/clint.h> + +#ifdef CONFIG_64BIT +static inline cycles_t get_cycles(void) +{ + return readq_relaxed(clint_time_val); +} +#else /* !CONFIG_64BIT */ +static inline u32 get_cycles(void) +{ + return readl_relaxed(((u32 *)clint_time_val)); +} +#define get_cycles get_cycles + +static inline u32 get_cycles_hi(void) +{ + return readl_relaxed(((u32 *)clint_time_val) + 1); +} +#define get_cycles_hi get_cycles_hi +#endif /* CONFIG_64BIT */ + +/* + * Much like MIPS, we may not have a viable counter to use at an early point + * in the boot process. Unfortunately we don't have a fallback, so instead + * we just return 0. + */ +static inline unsigned long random_get_entropy(void) +{ + if (unlikely(clint_time_val == NULL)) + return 0; + return get_cycles(); +} +#define random_get_entropy() random_get_entropy() + +#else /* CONFIG_RISCV_M_MODE */ + static inline cycles_t get_cycles(void) { return csr_read(CSR_TIME); @@ -41,6 +79,8 @@ static inline u64 get_cycles64(void) } #endif /* CONFIG_64BIT */ +#endif /* !CONFIG_RISCV_M_MODE */ + #define ARCH_HAS_READ_CURRENT_TIMER static inline int read_current_timer(unsigned long *timer_val) { |